Green’s Dictionary of Slang

(US) sanctimonious.

1929		C. McKay Banjo 150: Feeling uneasy under her strange, holy-rolling eyes.
1965		(con. 1944) E.M. Nathanson Dirty Dozen (2002) 33: You holy-rolling son-of-a-bitch, you’re the worst of all!
1981		P. Radley Jack Rivers & Me 43: [T]he holy-rolling Joneses and their relations.